Yep - I keep a stock of them in my pantry alongside a few other items I wouldn't have tried the first time if they hadn't been free after the coupons:
Reynolds Release foil - regular foil is only for wrapping thing goinf into the oven, or covering in the oven. Release really does work - no more Tater tots sticking to the foil.
Glad Press & Seal - love this stuff. it costs more, but I don't use nearly as much as the "cling wrap" products. Look for the seasonal prints after the fact - Target and sometime Walmart clear them out with other seasonal stuff. I got my first few boxes 75% off - they were a spring print, and were clearanced in June or July with other "spring" items. They do the same with printed theme ziploc sandwich bags (think halloween, particularly).
The really BIG ziploc bags. I use them for clothing going into storage, kind of like the vac bags - if you can compress the extra air out.
What's nice with the crock-pot bags is that you can prep the meal ahead in the bag, and store in the fridge until you're ready to use it, without using up so much space. Then just put the bag into the crockpot, and set it to cook. I might even try that next vacation - prep everything ahead, and throw into the cooler in the bags.